Helical tomography is the integration of radiotherapy and helical computed tomography. It has the potential to provide improved verification of each intensity modulated treatment. New processes for the improved delivery verification have recently been proposed to provide unprecedented image-guidance for radiation therapy and this work will research, develop and test these processes using a unique tomotherpay research benchtop system and the world's first clinical helical tomotherapy unit. Helical tomotherapy and its verification processes will make dose per fraction escalation possible when the critical normal tissue dose per fraction may be verified to be kept below levels which would cause undue harm. The verification processes will make daily treatments more precise as well as be able to determine delivery errors and adapt subsequent treatments more precise as well as be able to determine delivery errors and adapt subsequent treatments to account for the errors. The processes will enable aggressive conformal avoidance therapy as well as conformal radiotherapy treatments to be accurately verified. This will in turn give more confidence to the results of clinical trials.